Double shell structure for air pumps

ABSTRACT

A double shell structure for air pumps has an outer shell and an inner shell housed in the outer shell for installing an air pump body. The double shell structure can effectively reduce noise leakage resulting from air pump operation.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention relates to the shell structure of air pumps andparticularly to air pumps that have a double shell structure forreducing noise leakage during operation.

[0003] 2. Description of the Prior Art

[0004] Conventional shell structure for air pumps (referring to FIG. 1)generally includes a shell 2 consisting of an upper lid 21 and a base22. The shell 2 has a hollow housing chamber 20 located inside forinstalling the body 1 of an air pump. When the air pump body 1 operates,air is discharged through an air duct 11 into an aquarium for use. Sucha structure generates a greater noise when the air pump body 1 operates.It becomes an annoyance in house environments. While breeding pet fishcan enhance environmental aesthetics and provide visual amusement, thegenerated noise spoils house serenity.

SUMMARY OF THE INVENTION

[0005] In view of the aforesaid disadvantages, the object of theinvention is to provide a double shell structure for air pumps to reducethe noise leakage during air pump operation.

[0006] The double shell structure of the invention mainly has an innershell housed in an outer shell. The air pump body is installed in theinner shell. By means of the double shell structure, leakage of noisegenerated by the air pump during operation may be effectively reduced.

[0007] The foregoing, as well as additional objects, features andadvantages of the invention will be more readily apparent from thefollowing detailed description, which proceeds with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008]FIG. 1 is a sectional view of a conventional air pump.

[0009]FIG. 2 is an exploded view of the invention.

[0010]FIG. 3 is a sectional view of the invention.

[0011]FIG. 4 is a sectional view of another embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Referring to FIGS. 2 and 3, the invention mainly includes anouter shell 31 and an inner shell 32 located in the outer shell. Theouter shell 31 and the inner shell 32 are interposed by a hollow space310. The inner shell 32 has a hollow housing chamber 320 for installingan air pump body 4. The outer shell 31 consists of an outer upper lid311 and an outer base 312 coupling together. The outer base 312 has atop edge forming an indented coupling rim 3124. A sealing gasket 34 ismounted on the coupling rim 3124 to couple with another coupling rim3112 formed on the inner side of the bottom edge of the outer upper lid311 to form a seal to enhance noise insulation effect. Then screws 3123are engaged with screw holes 3121 to fasten the outer upper lid 311. Theouter upper lid 311 further has at lest one semi-circular opening 3111on the lateral side corresponding to at least one semi-circular opening3122 on the outer base 312 to form at least one air discharge anchorhole A (the number of the hole depends on the number of air dischargeducts of the air pump body 4). The inner shell 32 has an inner base 322to couple with an inner upper lid 321. The inner base 322 has a hollowchamber 320 for installing the air pump body 4, and one lateral sidehaving at least one notch 3221 to enable an air discharge duct 41 to runthrough to connect to an elbow duct 42. The elbow duct 42 has anotherend connecting to another air discharge duct 43 which couples with aduct sleeve 44 for discharging air. The inner upper lid 321 has adownward recess with a lid peripheral rim 3214 slightly larger than theouter peripheral rim of the inner base 322. The inner upper lid 321further has an opening 3211 to allow an air inlet duct 35 to runthrough. The air inlet duct 35 has a lower section 351 running throughthe inner side of the inner upper lid 321 to couple with an opening 361of a thin sheet 36 (which serves to eliminate transmission of resonanceand reduce noise generation) and an opening 331 of a soft pad 33 suchthat the soft pad 33 may be in contact with the top rim of the innerbase 322. Then the inner upper lid 321 may be closed and fastenedthrough engaging screws 3213 into the apertures 3212 and 332 of theinner upper lid 321 and the soft pad 33 and the screw holes 3222 of theinner base 322, thereby to fasten the inner upper lid 321 tightly to theinner base 322.

[0013] By means of the construction set forth above, when the air pumpbody 4 operates (air pump operation is known in the art and forms nopart of the invention, thus details are omitted), vibrations and noisesoccur. Through the double sealing structure of the inner shell 32 andouter shell 31, most noise leakage are eliminated, thus noise annoyingproblem can be effectively resolved.

[0014] Refer to FIG. 4 for another embodiment of the invention. An outershell 31′ includes an outer upper lid 311′ to cover an outer base 312′.An inner shell 32′ is housed in the outer shell 31′. The inner shell 32′has a hollow housing chamber 320′ for installing an air pump body 4′.The outer shell 31′ and the inner shell 32′ are interposed by a hollowspace 310′. The inner side of the outer upper lid 311′ has an indentedand downward lid rim 3110′ to hold a soft pad 33′ for covering to thetop rim of the inner shell 32′. The inner shell 32′ has at least onenotch 3210′ to enable an air discharge duct 41′ to run through.

[0015] By means of the construction set forth above, noise resultingfrom vibrations during air pump operation may be reduced from leakingout. Thus people can enjoy the pleasure of breeding pet fish and theserenity of the house can be maintained.

I claim:
 1. A double shell structure for air pumps comprising an outershell and an inner shell housed in the outer shell, the outer shell andthe inner shell being interposed by a hollow space therebetween, theinner shell having a hollow housing chamber for installing an air pumpbody such that noise resulting from operation of the air pump body isreduced from leaking through the inner shell and the outer shell.
 2. Thedouble shell structure for air pumps of claim 1, wherein the outer shellincludes an outer upper lid and an outer base.
 3. The double shellstructure for air pumps of claim 1, wherein the inner shell includes aninner upper lid and an inner base.
 4. The double shell structure for airpumps of claim 3, wherein the inner base has a lateral side which has atleast one notch forming thereon.
 5. The double shell structure for airpumps of claim 3, wherein the inner upper lid has a downward recesswhich has a lid peripheral rim slightly larger than the outer peripheralrim of the inner base.
 6. The double shell structure for air pumps ofclaim 5, wherein the inner base has a top rim in contact with a softpad, and the inner upper lid being covered on the soft pad to achieve atightly sealing.
 7. The double shell structure for air pumps of claim 6,wherein the inner upper lid has an opening to allow an air inlet duct torun through.
 8. The double shell structure for air pumps of claim 7,wherein the soft pad and the inner upper lid are interposed by a thinsheet which has an opening to couple with a lower section of the airinlet duct.
 9. A double shell structure for air pumps comprising anouter shell and an inner shell housed in the outer shell, the outershell and the inner shell being interposed by a hollow spacetherebetween, the inner shell having a hollow housing chamber forinstalling an air pump body, the outer shell having an outer upper lidwhich has an inner side forming a downward rim surrounding a recess forhousing a soft pad to allow the outer upper lid to cover the top rim ofthe inner shell to increase tightly fastening effect.
 10. The doubleshell structure for air pumps of claim 9, wherein the inner shell has atleast one notch to allow an air discharge duct to run through.